Blue disazo-dye and process of making same.



UNITED STATES Pi rnn'r OFFICE.

AUGUST LEOPOLD LASKA, OF OFEENBiiOILON-THE-MAIN, GERMANY, ASSIGNOR TO GHEMISCHE FABRIK GRIESHEIM-ELE KTRON, OF FRANKFORT-ON-THE-MAIN, GER- MANY, A CORPORATION.

. BLUE 'msAzo-DYE AND rnocnss or usrcme SAME.

dye cotton violet to blue tints of excellent brightness surpassing in this point similar commercial azodyestuffs. The 2 ary1amido 5 naphthol 7 sulionic acid em loyed in the manufacture of these dyestuffs ren ders them last to sodium carbonate, so that a neutral or alkaline bath can be used in dyeing;

' The following example will serve to illustrate the rim ture of my invention; parts being by weight: A solution of the tetiazo-compoundobtained from 12,2 partsof dianisidin in the well known manner is poured into'an ice cold alkaline solution of 17,4 parts of -l naphthel 3:6

disulioacid (neutral sodium salt) in 200 parts oi water, and alter formation of the intermediate product a solution of 16 parts of 2 phenylamido 5 naphthol 7 sulioacid,

neutralized by means of sodium carbonate, is added. The mixture is stirred for 12hours, heated up to 70 C. and the dye-stuff precipitated'by addition of common salt. The coloring matter, in a dry state being abla'cls powder, dissolves in concentrated sulfuric acidtoa greenish blue, in water to a reddish blue solution. The color of this solution is hardly altered by addition of caustic ziodalye or hydrochloric acid. Orr-cotton the dyestuff produces very bright blue tints. i

In place of the 1 naphthol 3:6 'disulfoaeid naphthol Specification of Letters Patent. Application filed March 22,1907. Serial No. 363,940.

Patented July 10, 1907.

sold dinmidobnses with one rnoiernlnr proportion 01 u nuphthol disulfoucid and one molecular proportion of 2 nryinlnido =--.5 naphthol 7 sulfuncid.

2 The process of nmiiufucluring new cotton dyrstuli's. which consists in combining the tetrazueompound of diunisidln with one inolecuinr proportion of a nuphihol disuilmu-id and one molecular proportion of 2 arylumldo 5 imphthoi 7 sulfoacid.

3. As :1 new article of manufacture the :izocolorlnt: matter obtained by combining llie lifliI'HZOLUIHPUUIKT(Ii: (l l-' unisidln with one moloenlnr proportion of u nnphthol disulfougid and one molecular proportion of urylmnido 5 nnphlhol 7 sullonrld, being a block po'wdor dissolving in concentrated sulfuric lll'ltl to n greenish blue in water to n reddish blue solulion, nod dyeing cotton very bright blue shades.

4. his n new article of manufacture the dyestuffs on:

- :ield rind ooh molecular proportion of 2 urylumldo 5 nnplr tliol 7 suli'onid, being biuekpowdern, dissolving in concentruled sulfuric :u-l'd to u greenish blue, in water to n reddish blue solution, nnd dyeing eotlon very bright blue nhudcs.

in testimony, that l eln'lm'lhe foregoing as my lnvenlion, 1 have signed my mime in presence of two wil.uu.--i:-ie:4, this seventh day of March 1907.

I AUHl'lS'l LEUl 'OLD LASKA.

Witnesses v I Eva S.\'r'rhni ilnmuxu 'IHL. 

